Center hung radiant tube supports

ABSTRACT

A unitary cast bracket for supporting radiant heating tubes centrally within indirectly heated furnaces comprising a channel and a plurality of flanges and webs arranged to support the tubes along a tangential seat.

v United States Patent Inventor Roger C. Stephens Hamburg, N.Y.

App]. No. 41,469

Filed May 28, 1970 Patented Aug. 17, 1971 Assignee Ferro Frontiers, Inc.

Buffalo, N.Y.

CENTER HUNG RADIANT TUBE SUPPORTS 3 Claims, 2 Drawing Figs.

US. Cl 248/58, 248/68 Int. Cl F16] 3/02 Field of Search 248/68, 58,

References Cited UNITED STATES PATENTS 11/1931 Miller 248/68X 5/1936 Hepburn l26/91AX 10/1939 Brown 122/510 8/1944 Hensel 122/510 9/1962 Hamilton... 122/510 Primary Exarr1iner--Chancellor E. Harris AttorneyWebb, Burden, Robinson & Webb ABSTRACT: A unitary cast bracket for supporting radiant heating tubes centrally within indirectly heated furnaces comprising a channel and a plurality of flanges and webs arranged to support the tubes along a tangential seat.

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CENTER HUNG RADIANT TUBE SUPPGRTS BACKGROUND I Numerous indirectly heated furnaces used in industry are designed with Special facilities for'controlling theatmosphere in the working chamber. For example, heat-treating furnaces are used in the steel industry for-such processes as-annealing, normalizing, spheroidizing, hardening, tempering, carburizing, and stress relieving. The atmosphere within thefurnace must be controlled in order to obtain desired surfaceconditions. For these processes, heat-treating furnaces seldom are designed for temperatures in. excess of 2,000 E, andgenerally operate in the 800 F. to the'l',600 F. range. They are. usually well insulated and built to minirnizeair infiltration or loss of special atmospheres. V

In heat-treating furnaces of the annealing .type, means for controlling'the rate of heating and cooling of the workpieces usually are provided. Insulating brick or monolithic linings generally are used in heat-treatingfurnace construction due to their low heat storage capacity thus permitting rapid heating and cooling of the furnace.

This invention pertains to controlled atmosphere heat-treating furnaces heated by radiant heating tubes. Radiant heating tubes are commonly used for indirect firing, especially where the temperature seldom exceeds the 800 F. to 1,600 F. range. The tubes are supported in place by special brackets or supports. The tubes and the brackets generally'arecomprised of special alloy materials to reduce the maintenance of these parts to a minimum. Notwithstanding the use ofcarefully selected alloys for the brackets, as a result of the'continual raising and lowering of the temperature gradient through the brackets and other factors, after a period of time they have tended to fail by cracking and in other' ways. Failure of-a bracket may be disastrous-as. it may permit a radianttubeto fall or break open and thereby contaminate theatmosphere within the furnace.

One very common application of the radiant tube-type heating is in the radiant tube firedcovered-type furnace employed in the heat treating of coils offlat-rolled products. In these furnaces the top and four, sidewalls comprise a unitary removable cover which canbe raised away from the base upon-which the coil products are positioned for treatment. Radiant tubes are positioned along at least two sides of the cover andarehung' from the center of thecover roof. This inventionisvdirected primarily to the center hungbrackets for supporting'radiant heating tubes from the roof of furnaces and especially in furnaces wherein the roof and sidewalls comprise a removable cover. My copending application filed of even date entitled- RADIANT TUBE SUPPORTS is directed to the bracketsfor been complicated structurescomprising two elongate facing.

sections which were bolted together (with clamps :located between bolts) around a battery of radiant heating tubes. The

complexity of the design has been an unfortunate drawback. The bolting and clamping, was a time consuming process. Furthermore, if it was necessary toremove just one tube, the entire support bracket had to be disassembled and reassembled.

It is a feature according to this invention to provide-a unita ry cast bracket for supporting radianttubes within-:heat treatz-z ing furnaces ofthetype described. It is a further feature-of this invention to providea tubebracket, which is more-durable; more easily manufactured, less complicated to .use, and 'a bracket which has the ability to hold radiant tubes in place in' the center of a controlled atmosphere furnace when the furnace is being transported from place to place.

BRIEF DESCRIPTION Briefly, according to this invention, there-is provided a unitary cast bracket hung from the roof of an indirectly heated furnace for-supporting radiant heating tubes or the like. The bracket comprises an upright channel preferably having spaced stiffening webs'therein. Secured to the top of the channel is a fastening means for securing, for example, by bolting, th'e'bracket to the roof of the furnace.

A plurality of paired upper and lower tube support flanges are secured to and extend away from the upright channel. The tube support flanges are arranged to provide a tangential seat for 'the radial heating tubes. Upper and lower restraining webs are" shaped to restrain the movement of the radiant tubes toward and away from the upright channel while accommodating thermal expansion of the tubes and bracket.

The paired upper and lower restraining webs have spaced substantially parallel edges such that the parallel radiant heatingtubes having a fixed spatial relation therebetween may be DETAILED DESCRIPTION Further features and other objects and advantages of this invention will become clear from the following detailed description made with'reference to the drawings in which:

FIG. 1 is a pictorial view of a bracket according to a preferred embodiment of this invention.

FIG. 2is'a side view of'a bracket according to this invention.

Referring nowtoFIG. 1, the unitary cast bracket comprises an'upright'elongate channel 1. Preferably, the channel has spacedsupporting webs'2 therein. Secured to the top of the channel isa fastening means 3 comprising a horizontal flange 4; supporting webs5, and fastening flanges 6 and 7, having openings8therethrough for receiving a suitable fastener (not shown). Additional supporting webs 9 may extend between the' horizontal flange 4 and the uppermost restr'ainingweb' pairs of supportflanges. The tube support flanges are arranged to provide a tangential seat for radiant heating tubes. By tangential seat is meant the support flange is tangent to the surface of the radiant heating tubes. In this way, the tubes during mostconditions will only contact the bracket along 'three lines shown in FIG. 1 as dashed lines 15, 16 and 17. Hence, the heat transfer by conduction from the radiant heating tubes to the bracketis slowed.

Lower restraining webs 13 are shaped to restrain the move-' ment of the radiant tube seated on a lower support flange toward and away from the channel while accommodating thermal expansion of the tube' and the bracket. Lower restraining webs are secured at their edges to the upright channel and an upper and a lower support flange. Upper restraining-webs '14 are shaped to restrain the movement of the-radiant tube seated on upper support flanges toward and away-from the channel; The upper restraining webs 14, with thecxception of the uppermost upper restraining web, are secured'at their edges to the upright channel and an upper and a lowersupport flange; The uppermost upper restraining web is secured at its edges to the upright channeL'an upper support fla'nge and-horizontal flange'4. The restraining' webs (upper or lower)-are= actually two-part webs separated to'permit' the support-flanges to provide a tangential seat; The edge surfaces 13a and l4a of the restraining webs are curvilinear, preferably circular having a center of curvature at about'the center of curvature of the radiant heating tubes when seated on the tube support flanges. The edge surfaces 13b, 13c, 14b and 140 are preferably parallel to each other.

The channel 1 extends below the lowermost lower support flange. At or near the bottom of the channel a base flange 20 extends away from the face 12. A support web 21 is secured to the'lowermost lower support flange, the channel and the base flange. An opening 22 is preferably provided in the support web 21 through which a pipe may be passed to secure two spaced brackets together at the lower ends. 1

Throughout the specification and the claims, the webs and flanges and channel comprising the bracket according to this invention have been described as secured to each other. It should, or course, be understood that the webs and flanges are not separately formed and joined, but are cast as one unitary member.

Referring now to FIG. 2, it is a side view of brackets according to this invention demonstrating the position of a radiant heating tube (shown in section). The substantially parallel edge surfaces 13b, 13c, 14b and 140 of the restraining webs are shown in FIG. 2, and the manner in which the U-shaped radiant heating tubes 25 may be inserted in the webs is also shown by the dashed lines having arrows at each end.

It should, of course, be clear to one skilled in the art that the edge surfaces of the restraining webs 13b, 130, 14b and 140, which have been referred to as substantially parallel, may also be nonparallel, so long as the restraining webs of paired upper and lower support flanges provide spaced parallel pathways for the insertion of the U-shaped combustion tubes into the bracket. The pathways should preferably form an angle of between 30 and 60 with the plane of the upright channel 1. Having thus defined my invention in detail with the particularity required by Patent Laws, what is desired to have protected by Letters Patent are set forth in the following claims.

I claim:

1. A unitary cast bracket for hanging radiant heating tubes from the roof of an indirectly heated furnace, said bracket comprising:

an upright elongate channel;

means for securing the top of the upright channel to the furnace roof;

a plurality of paired upper and lower tube support flanges secured to and extending away from the upright channel, the said tube support flanges arranged to provide a tangential seat for the radiant tubes;

a plurality upper and lower restraining webs shaped to restrain the movement of radiant tubes toward and away from the channel while accommodating thermal expansion of the tubes and bracket, said restraining webs secured at their edges to the upper and lower support flanges, the restraining webs being shaped to provide parallel pathways for the insertion of U-shaped radiant heating tubes.

2. The bracket according to claim 1 wherein the webs all lie substantially in the same plane and the flanges and the face of the upright channel are substantially perpendicular to said webs.

I 3. The bracket according to claim 1 wherein the parallel pathways form an angle between 30 and 60 with the upright channel. 

1. A unitary cast bracket for hanging radiant heating tubes from the roof of an indirectly heated furnace, said bracket comprising: an upright elongate channel; means for securing the top of the upright channel to the furnace roof; a plurality of paired upper and lower tube support flanges secured to and extending away from the upright channel, the said tube support flanges arranged to provide a tangential seat for the radiant tubes; a plurality upper and lower restraining webs shaped to restrain the movement of radiant tubes toward and away from the channel while accommodating thermal expansion of the tubes and bracket, said restraining webs secured at their edges to the upper and lower support flanges, the restraining webs being shaped to provide parallel pathways for the insertion of U-shaped radiant heating tubes.
 2. The bracket according to claim 1 wherein the webs all lIe substantially in the same plane and the flanges and the face of the upright channel are substantially perpendicular to said webs.
 3. The bracket according to claim 1 wherein the parallel pathways form an angle between 30* and 60* with the upright channel. 